An American college student has spoken out for the first time ­following his release from a ­week-long detention in China for allegedly injuring a taxi driver who was roughing up his mother ­during a fare dispute.

Guthrie McLean, a student at the University of Montana, was released from jail in Zhengzhou in Henan province early on Monday, according to his mother Jennifer McLean, a teacher who lives in the Chinese city.

In a post-release interview with the Montana newspaper Missoulian, Guthrie McLean described feeling “happy, frustrated, and overwhelmed” about the entire situation, which took place while he was visiting his mother.

McLean, who is planning to ­return to the US on August 29, said police had told him there was no proof the taxi driver hurt his mother, whereas the driver had sustained injuries.

“This incident was done as part of the actions of a taxi driver and a few old-fashioned-thinking police officers,” he told the paper.

The release followed an agreement with the Chinese authorities to drop any charges against Guthrie Mclean, according to Montana US Senator Steve Daines.

Further details on the agreement were not immediately disclosed. Local police in China have declined to comment on the case.

“We are very, very, very, very happy,” Jennifer McLean wrote in an email. She said the release – at 2 am – came as a surprise after she had twice previously been told to anticipate a release only to be disappointed.

“They have not finished the process completely, but we are hopeful it will go smoothly from here on.

Daines plus US Senators Jon Tester and Congressman Greg Gianforte had pressed McLean’s case with China’s Ambassador to the US Cui Tiankai and Secretary of State Rex Tillerson.

The lawmakers said McLean had been justifiably defending his mother, who is deaf, from the driver, whose knee was reportedly hurt in the encounter.

Jennifer McLean said the taxi driver had been pushing her around and hurting her when her son intervened and pushed him to the ground.

Jennifer McLean said that when police detained Guthrie five weeks later on charges of intentional injury, they demanded the equivalent of 50,000 yuan (US$7,400) in compensation and threatened to imprison her son for up to three years if they refused to pay.

The family did not pay the sum, according to Daines, who added that more details would be released at a later time.

“After two 20-hour days in back and forth negotiations with Chinese officials, we were able to come to an agreement that worked for everybody, most importantly for Guthrie and for Jennifer, his mother,” Daines said in a conference call with reporters.

Daines said he spoke with Guthrie McLean after his release and he plans to return to Missoula, Montana to resume his studies next month.

The State Department declined to comment on its involvement in the case or the agreement with Chinese authorities. Tester and Gianforte issued statements on Sunday saying they were pleased with the outcome of the case.

Guthrie McLean has been majoring in East Asian studies at the University of Montana in Missoula for about two years and works in the department of modern and classical languages and literatures, according to school officials.

He is a US citizen, but largely grew up in China after living in Missoula as a young child while his mother was studying at the university.

His friend and classmate Zakk Winch had co-organised a crowd funding effort for the family, raising US$655 to help pay off the US$7,500, the police were originally requesting.

Olivia White, McLean’s supervisor at his university department told the South China Morning Post earlier that his detention had come as a shock.

“He is a very gentle, thoughtful soul. He is also keenly aware of Chinese politics and as an American living in China, is quite careful about his actions,” she said.